Recent advances in casing/liner rotational orientation in a well allow for pressure pulse telemetry to communicate orientation data to surface via encoded negative pressure pulses. However, a pressure differential is needed between an interior and an exterior of the casing/liner in order to produce the pressure pulses. For this reason and others, advancements are continually needed in the art of regulating flow through a well tool string. Such advancements may be useful whether or not a casing/liner is rotationally oriented using pressure pulse telemetry to encode orientation data on negative pressure pulses.